<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <script src="https://cdn.jsdelivr.net/npm/vue@2/dist/vue.js"></script>
  <style>
    b {
      padding: 6px 12px;
    }
    .active {
      color: red;
    }
  </style>
</head>

<body>
  <div id="app">
    <div>
      <b v-for="(v,i) in tabs" 
        v-bind:class="i === activeIndex ? 'active': ''"
        v-on:click="activeIndex=i"
        >{{ v.title }}</b>
    </div>
    <div>
      <ul>
        <li v-for="v in tabs[activeIndex].children">{{ v }}</li>
      </ul>
    </div>
  </div>  
  <script>
    let vm = new Vue({
      el: '#app',
      data: {
        tabs: [{
          title: '英雄联盟',
          children: ['亚索', '剑圣', '石头人']
        }, {
          title: '王者荣耀',
          children: ['安其拉', '赵云', '曹操']
        }, {
          title: 'data2',
          children: ['剑圣', 'SF']
        }],
        activeIndex: 2
      }
    })
  </script>
</body>

</html>